If they score everyone against “the average” you will find the best performers in the group with their ankles broken.
Managing against standard deviations from the mean is OK, but expecting everyone to be above an average is mathematically impossible.
True, there’s no way everyone can be above average.
does Amazon accept high turnover as a cost of doing business, as they seek to have a high achieving workforce? Perhaps that is their business model as it pertains to their workers.